Search

Introduction: This study examined (1) whether measures of paternal anxious and depressive symptoms collected prenatally and during a follow-up assessment when the child was in middle childhood, predict child neuroendocrine outcomes, and (2) whether neuroendocrine outcomes are intermediate factors between paternal mental health and child cognitive/behavioral outcomes. Middle childhood coincides with increased autonomy as the child transitions into grade school, and with adrenarche, as the maturing adrenal gland increases secretion of dehydroepiandrosterone (DHEA) and its sulfated metabolite (DHEA-S), hormones that are implicated in corticolimbic development which regulate emotions and cognition., Methods: Participants were recruited from a subsample of a large prospective birth cohort study (3D study). We conducted a follow-up study when children were 6-8 years old ( N  = 61 families, 36 boys, 25 girls). Parental symptoms of anxiety, stress and depression were assessed via validated self-report questionnaires: prenatally using an in-house anxiety questionnaire, the Perceived Stress Scale (PSS) and the Center for Epidemiologic Studies Depression (CES-D), and at the follow up, using the Beck Anxiety and Beck Depression Inventories. Children provided salivary hormone samples, and their pituitary gland volume was measured from structural Magnetic Resonance Imaging (MRI) scans. Child behaviors were measured using the Strengths and Difficulties Questionnaire and cognitive outcomes using the WISC-V. Multiple regression analyses were used to test whether paternal mental health symptoms assessed prenatally and during childhood are associated with child neuroendocrine outcomes, adjusting for maternal mental health and child sex. Indirect-effect models assessed whether neuroendocrine factors are important intermediates that link paternal mental health and cognitive/behavioral outcomes., Results: (1) Fathers' prenatal anxiety symptoms predicted lower DHEA levels in the children, but not pituitary volume. (2) Higher prenatal paternal anxiety symptoms predicted higher child internalizing symptoms via an indirect pathway of lower child DHEA. No associations were detected between paternal anxiety symptoms measured in childhood, and neuroendocrine outcomes. No child sex differences were detected on any measure., Conclusion: These results highlight the often-overlooked role of paternal factors during pregnancy on child development, suggesting that paternal prenatal anxiety symptoms are associated with child neuroendocrine function and in turn internalizing symptoms that manifest at least up to middle childhood., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Jones, De Braga, Caccese, Lew, Elgbeili, Castellanos-Ryan, Parent, Muckle, Herba, Fraser, Ducharme, Barnwell, Trasler, Séguin, Nguyen and Montreuil.)

Importance: Alcohol consumption is one of the leading preventable causes of burden of disease worldwide. Selective prevention of alcohol use can be effective in delaying the uptake and reducing harmful use of alcohol during the school years; however, little is known about the durability of these effects across the significant transition from early adolescence into late adolescence and early adulthood., Objective: To examine the sustained effects of a selective personality-targeted alcohol use prevention program on alcohol outcomes among adolescents who report high levels of 1 of 4 personality traits associated with substance use., Design, Setting, and Participants: A cluster randomized clinical trial was conducted to assess the effectiveness of the selective personality-targeted PreVenture program on reducing the growth of risky alcohol use and related harms from early to late adolescence and early adulthood. Participants included grade 8 students attending 14 secondary schools across New South Wales and Victoria, Australia, in 2012 who screened as having high levels of anxiety sensitivity, negative thinking, impulsivity, and/or sensation seeking. Schools were block randomized to either the PreVenture group (7 schools) or the control group (7 schools). The primary end point of the original trial was 2 years post baseline; the present study extends the follow-up period from July 1, 2017, to December 1, 2019, 7 years post baseline. Data were analyzed from July 22, 2021, to August 2, 2022., Interventions: The PreVenture program is a 2-session, personality-targeted intervention designed to upskill adolescents to better cope with their emotions and behaviors., Main Outcomes and Measures: Self-reported monthly binge drinking, alcohol-related harms, and hazardous alcohol use measured by the Alcohol Use Disorders Identification Test-Concise consumption screener., Results: Of 438 participants (249 male [56.8%]; mean [SD] age, 13.4 [0.5] years) from 14 schools, 377 (86.2%) provided follow-up data on at least 2 occasions, and among those eligible, 216 (54.0%) participated in the long-term follow-up. Compared with the control condition, the PreVenture intervention was associated with reduced odds of any alcohol-related harm (odds ratio [OR], 0.81 [95% CI, 0.70-0.94]) and a greater mean reduction in the frequency of alcohol-related harms (β = -0.22 [95% CI, -0.44 to -0.003]) at the 7.0-year follow-up. There were no differences in the odds of monthly binge drinking (OR, 0.80 [95% CI, 0.56-1.13]) or hazardous alcohol use (OR, 0.87 [95% CI, 0.59-1.27]) at the 7.0-year follow-up. Exploratory analyses at the 5.5-year follow-up showed that compared with the control condition, the PreVenture intervention was also associated with reduced odds of monthly binge drinking (OR, 0.87, [95% CI, 0.77-0.99]) and hazardous alcohol use (OR, 0.91 [95% CI, 0.84-0.99]), but this was not sustained., Conclusions and Relevance: This study demonstrated that a brief selective personality-targeted alcohol use prevention intervention delivered in the middle school years can have sustained effects into early adulthood., Trial Registration: anzctr.org.au Identifier: ACTRN12612000026820.

Commonly comorbid early onset psychiatric disorders might reflect the varying expression of overlapping risk factors. The mediating processes remain poorly understood, but three factors show some promise: adolescent externalizing traits, early life adversity, and midbrain dopamine autoreceptors. To investigate whether these features acquire greater predictive power when combined, a longitudinal study was conducted in youth who have been followed since birth. Cohort members were invited to participate based on externalizing scores between 11 to 16 years of age. At age 18 (age 18.5 ± 0.6 y.o.), 52 entry criteria meeting volunteers had a 90-min positron emission tomography scan with [ 18 F]fallypride, completed the Childhood Trauma Questionnaire, and were assessed with the Structured Clinical Interview for DSM-5. The three-factor model identified those with a lifetime history of DSM-5 disorders with an overall accuracy of 90.4% (p = 2.4 × 10 -5 ) and explained 91.5% of the area under the receiver operating characteristic curve [95% CI: .824, 1.000]. Targeting externalizing disorders specifically did not yield a more powerful model than targeting all disorders (p = 0.54). The model remained significant when including data from participants who developed their first disorders during a three-year follow-up period (p = 3.5 × 10 -5 ). Together, these results raise the possibility that a combination of temperamental traits, childhood adversity, and poorly regulated dopamine transmission increases risk for diverse, commonly comorbid, early onset psychiatric problems, predicting this susceptibility prospectively., (© 2021. The Author(s), under exclusive licence to American College of Neuropsychopharmacology.)

Importance: Household food insecurity has been associated with mental health problems in children independently of family income and other confounders. It is unclear whether food insecurity during childhood is also associated with mental health and functioning during adolescence., Objective: To evaluate longitudinal trajectories of household food insecurity during the first 13 years of life, characteristics associated with these trajectories, and the associations of the trajectories with externalizing, internalizing, substance use, and social adjustment problems at 15 years of age., Design, Setting, and Participants: This cohort study included participants from the Québec Longitudinal Study of Child Development, a cohort of 2120 children born in Québec, Canada, in 1997 and 1998 and followed up annually or biannually from 5 months to 15 years of age (1998-2013). Data were analyzed from November 2020 to October 2021., Exposures: When children were aged 1.5, 4, 8, 10, 12, and 13 years, mothers reported whether a family member experienced hunger because the family had run out of food or money to buy food in the past 12 months., Main Outcomes and Measures: Group-based trajectory modeling was used to identify differential exposure to food insecurity from 1.5 to 13 years according to logit functions of age. At 15 years of age, adolescents completed validated questionnaires assessing externalizing, internalizing, substance use, and social adjustment problems. Associations between trajectories of food insecurity and outcomes were assessed using linear regressions., Results: A total of 2032 individuals were included in the analyses of trajectories of food insecurity (1026 [50.5%] male) and 1441 in the analysis of the association with outcomes at 15 years of age (752 [52.2%] female). Two trajectories of food insecurity were identified between 1.5 and 13 years of age: high risk (73 children [3.6%]) and low risk (1959 children [96.4%]). At 5 months, the high-risk and low-risk groups differed in household characteristics including income insufficiency (58 [80.6%] vs 405 [21.0%]), single parenthood (21 [29.2%] vs 135 [6.9%]), and parental history of depression (mothers: 30 [43.5%] vs 411 [21.7%]; fathers: 12 [32.4%] vs 209 [13.5%]). The high-risk trajectory from 1.5 to 13 years of age was associated with cannabis use (β, 0.47; 95% CI, 0.12-0.81), peer bullying (β, 0.43; 95% CI, 0.08-0.77), and dropout potential (β, 0.38; 95% CI, 0.03-0.68) at 15 years of age after adjustment for sex, household income insufficiency, and parental mental health., Conclusions and Relevance: In this cohort study, few children experienced a persistent high risk of food insecurity, which was associated with psychosocial problems later in adolescence after adjustment for confounders including low income. Early identification of risk for food insecurity may guide the delivery of tailored interventions to improve functioning in adolescence.

The prevalence of mental health problems represents a significant burden on school and community health resources as early as preschool. Reducing this burden requires a better understanding of the developmental mechanisms linking children's early vulnerabilities with mental health after the transition to formal schooling. The 3D-Transition Study (2017-2021) follows 939 participants from a pregnancy cohort in the province of Québec, Canada, as they transition to kindergarten and first grade to examine these mechanisms. Biannual assessments include completed questionnaires from 2 parents as well as teachers, parent-child observations, anthropometric measurements, and age-sensitive cognitive assessments. Saliva is also collected on 11 days over a 16-month period in a subsample of 384 participants to examine possible changes in child salivary cortisol levels across the school transition and their role in difficulties observed during the transition. A combination of planned missing-data designs is being implemented to reduce participant burden, where incomplete data are collected without introducing bias after the use of multiple imputation. The 3D-Transition Study will contribute to an evidence-based developmental framework of child mental health from pregnancy to school age. In turn, this framework can help inform prevention programs delivered in health-care settings during pregnancy and in child-care centers, preschools, and schools., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: Only a minority of drug and alcohol users develops a substance use disorder. Previous studies suggest that this differential vulnerability commonly reflects a developmental trajectory characterized by diverse externalizing behaviors. In this study, we examined the relation between child and adolescent externalizing behaviors and adolescent substance use in a prospectively followed Canadian birth cohort, accounting for the temporal sequence of a wide variety of contributing factors., Methods: Two hundred and forty-two adolescents followed since birth (date range: 1996 to 2012) were assessed on externalizing behavior (age 17 months to 16 years), alcohol and cannabis use at age 16, age of alcohol use onset, family history of substance use problems, family functioning (age 11 to 15), sensation seeking (age 16), prenatal substance exposure, socioeconomic status (age 1 to 9), and sex., Results: Age of alcohol use onset was predicted by a family history of substance use problems, externalizing traits from ages 6 to 10 and 11 to 16, sensation seeking at age 16, prenatal alcohol and tobacco exposure and family functioning at ages 11 to 15. High frequencies of alcohol and cannabis use at age 16 were both predicted by externalizing traits from ages 11 to 16, a family history of substance use problems and sensation seeking after controlling for other individual, environmental and familial variables. The association between familial substance use problems and substance use during adolescence was partially mediated by externalizing traits from age 11 to 16., Conclusions: The present findings provide prospective evidence for a developmental risk pathway for adolescent substance use, potentially identifying those who could benefit from early interventions.

Background: Concerns have been raised that the COVID-19 pandemic could increase risk for adverse mental health outcomes, especially in young adults, a vulnerable age group. We investigated changes in depression and anxiety symptoms (overall and severe) from before to during the pandemic, as well as whether these changes are linked to COVID-19-related stressors and pre-existing vulnerabilities in young adults followed in the context of a population-based cohort., Method: Participants (n = 1039) from the Quebec Longitudinal Study of Child Development reported on their depression (Centre for Epidemiological Studies Depression Scale, short form) and anxiety (General Anxiety Disorder-7 Scale) symptoms and completed a COVID-19 questionnaire during the first wave of the COVID-19 pandemic in the summer of 2020 (age 22 years). Assessments at age 20 (2018) were used to estimate pre-pandemic depression and anxiety symptom severity., Results: While mean levels of depression and anxiety symptoms did not change from before to during the first wave of the COVID-19 pandemic (e.g., the mean of depressive symptoms was 9.30 in 2018 and 9.59 in 2020), we observed a slight increase in rates of severe depression (scores ≥ 21) from before (6.1%) to during (8.2%) the pandemic. Most COVID-19-related variables (e.g., loss of education/occupation, frequent news-seeking) - except living alone - and most pre-existing vulnerabilities (e.g., low SES, low social support) were not associated with changes in depression or anxiety symptoms. However, results varied as a function of pre-pandemic levels of depression and anxiety: depression and anxiety symptoms increased among adults with the lowest levels of symptoms before the pandemic, while they decreased among those with the highest levels of symptoms, possibly reflecting a regression to the mean., Conclusions: Depression and anxiety symptoms in young adults from Québec in Summer 2020 were mostly comparable to symptoms reported in 2018. Most COVID-19-related stressors and pre-existing vulnerabilities were not associated with changes in symptoms, except living alone and pre-existing symptoms of depression and anxiety. However, the increased rate of severe depression warrants further investigation., (© 2021. The Author(s).)

Background: Reviews and meta-analyses suggest that substance use and suicidality (i.e., suicidal ideations and attempts) are associated in youth, but the direction of this association remains unclear. Theoretically, the secondary psychiatric disorder hypothesis (SPDH) posits that substance use leads to suicidality, while the secondary substance use disorder hypothesis (SSUDH) posits that suicidality leads to substance use. To clarify these associations, this meta-analysis systematically reviewed studies that examined the prospective associations between SUDs and suicidality in youth (age 25 and younger) and compared results according to the direction of the association., Methods: Web of Science, Embase, PsycINFO, PubMed, Medline and ProQuest Dissertations & Theses Global were searched from inception to March 8, 2020, and 55 effect sizes from 23 samples were included and analyzed using a three-level meta-analysis., Results: SUDs significantly predicted subsequent suicidality (OR = 2.16, 95%CI 1.57-2.97), suicidality significantly predicted subsequent SUDs (OR = 2.16, 95%CI 1.53-3.04), and these effect sizes did not differ (p = 0.49)., Conclusions: Considering that 65% of reviewed studies only examined the SPDH, this review highlights that more attention should be given to the SSUDH, and that studies should examine bidirectional associations between SUDs and suicidality across time. Clinically, because SUDs and suicidality were found to influence each other, results suggest that mental health and SUDs should ideally be detected and treated early, and that co-occurring disorders should be assessed and treated concomitantly., Competing Interests: The authors have declared that no competing interests exist.

The excitatory neurotransmitter glutamate has been implicated in experience-dependent neuroplasticity and drug-seeking behaviors. Type 5 metabotropic glutamate (mGlu5) receptors might be particularly important. They are critically involved in synaptic plasticity and their availability has been reported to be lower in people with alcohol, tobacco, and cocaine use disorders. Since these reductions could reflect effects of drug use or pre-existing traits, we used positron emission tomography to measure mGlu5 receptor availability in young adults at elevated risk for addictions. Fifty-nine participants (age 18.5 ± 0.6) were recruited from a longitudinal study that has followed them since birth. Based on externalizing traits that predict future substance use problems, half were at low risk, half were at high risk. Cannabis use histories varied markedly and participants were divided into three subgroups: zero, low, and high use. Compared to low risk volunteers, those at elevated risk had lower [ 11 C]ABP688 binding potential (BP ND ) values in the striatum, amygdala, insula, and orbitofrontal cortex (OFC). Cannabis use by risk group interactions were observed in the striatum and OFC. In these regions, low [ 11 C]ABP688 BP ND values were only seen in the high risk group that used high quantities of cannabis. When these high risk, high cannabis use individuals were compared to all other participants, [ 11 C]ABP688 BP ND values were lower in the striatum, OFC, and insula. Together, these results provide evidence that mGlu5 receptor availability is low in youth at elevated risk for addictions, particularly those who frequently use cannabis.

The neurobiological traits that confer risk for addictions remain poorly understood. However, dopaminergic function throughout the prefrontal cortex, limbic system, and upper brainstem has been implicated in behavioral features that influence addiction vulnerability, including poor impulse control, and altered sensitivity to rewards and punishments (i.e., externalizing features). To test these associations in humans, we measured type-2/3 dopamine receptor (DA 2/3 R) availability in youth at high vs. low risk for substance use disorders (SUDs). In this study, N = 58 youth (18.5 ± 0.6 years) were recruited from cohorts that have been followed since birth. Participants with either high (high EXT; N = 27; 16 F/11 M) or low pre-existing externalizing traits (low EXT; N = 31; 20 F/11 M) underwent a 90-min positron emission tomography [ 18 F]fallypride scan, and completed the Barratt Impulsiveness Scale (BIS-11), Substance Use Risk Profile scale (SURPS), and Sensitivity to Punishment (SP) and Sensitivity to Reward (SR) questionnaire. We found that high vs. low EXT trait participants reported elevated substance use, BIS-11, SR, and SURPS impulsivity scores, had a greater prevalence of psychiatric disorders, and exhibited higher [ 18 F]fallypride binding potential (BP ND ) values in prefrontal, limbic and paralimbic regions, even when controlling for substance use. Group differences were not evident in midbrain dopamine cell body regions, but, across all participants, low midbrain BP ND values were associated with low SP scores. Together, the results suggest that altered DA 2/3 R availability in terminal extra-striatal and dopamine cell body regions might constitute biological vulnerability traits, generating an EXT trajectory for addictions with and without co-occurring alterations in punishment sensitivity (i.e., an internalizing feature).

The identification of different personality risk profiles for substance misuse is useful in preventing substance-related problems. This study aims to test the psychometric properties of a new version of the Substance Use Risk Profile Scale (SURPS) for Spanish college students. Cross-sectional study with 455 undergraduate students from four Spanish universities. A new version of the SURPS, adapted to the Spanish population, was administered with the Beck Hopelessness Scale, the UPPS-P Impulsive Behavior Scale, the State-Trait Anxiety Inventory (STAI) and the Alcohol Use Disorders Identification Test (AUDIT). Internal consistency reliability ranged between 0.652 and 0.806 for the four SURPS subscales, while reliability estimated by split-half coefficients varied from 0.686 to 0.829. The estimated test-retest reliability ranged between 0.733 and 0.868. The expected four-factor structure of the original scale was replicated. As evidence of convergent validity, we found that the SURPS subscales were significantly associated with other conceptually-relevant personality scales and significantly associated with alcohol use measures in theoretically-expected ways. This SURPS version may be a useful instrument for measuring personality traits related to vulnerability to substance use and misuse when targeting personality with preventive interventions.

The present study examined 1) whether the associations between cannabis use (CU) age of onset and drug abuse by 28 y remain when controlling for risk factors in childhood, adolescence and early adulthood; and 2) the developmental pathways from early risk factors to drug abuse problems. Participants from a longitudinal sample of boys of low socioeconomic status ( N = 1,030) were followed from 6 to 28 y. We examined the self-reported CU onset between the ages of 13 and 17 y and drug abuse symptoms by 28 y. The odds of developing any drug abuse symptoms by 28 y were reduced by 31% for each year of delayed CU onset (OR = 0.69). Cannabis, alcohol and other drug frequency at 17 y mediated this association. Still, even when taking that frequency of use into account, adolescents who started using cannabis before 15 y were at a higher risk of developing drug abuse symptoms by age 28 y. Significant indirect effects were found from early adolescent delinquency and affiliation with deviant friends to drug abuse symptoms at 28 y through CU age of onset and substance use frequency at 17 y. The results suggest more clearly than before that prevention programs should aim at delaying CU onset to prevent or reduce drug abuse in adulthood. Furthermore, prevention programs targeting delinquency and/or affiliation with deviant friends in childhood or early adolescence could indirectly reduce substance abuse in adulthood without addressing substance use specifically.

Atypical head circumference (HC) growth has been associated with neurodevelopmental disorders. However, whether it is associated with specific aspects of development in early childhood in the general population is unknown. The objective of this study was to assess the predictive value of HC growth as an early biomarker of behavioral traits. We examined longitudinal associations between HC growth from 0 to 12 months and temperament, cognitive, and motor development at 24 months. A subsample of healthy children (N = 756) was drawn from the 3D (Design, Develop, Discover) cohort study. Early HC growth was modeled with latent growth curve analysis. Greater postnatal HC growth predicted lower temperamental effortful control and lower surgency/extraversion in boys. HC growth did not predict cognitive or fine motor scores, but did predict greater gross motor skills in boys. No significant effect of HC growth was found in girls. This study is the first to demonstrate an association between postnatal HC growth and specific aspects of child development in a healthy population. Results suggest HC growth overshadows brain mechanisms involved in behavioral traits in early infancy. Whether links are maintained throughout development and the mechanisms involved correspond to traits found in atypical populations remains to be studied.

Background: Alcohol use and associated harms are among the leading causes of burden of disease among young people, highlighting the need for effective prevention. The Climate and Preventure (CAP) study was the first trial of a combined universal and selective school-based approach to preventing alcohol misuse among adolescents. Initial results indicate that universal, selective and combined prevention were all effective in delaying the uptake of alcohol use and binge drinking for up to 3 years following the interventions. However, little is known about the sustainability of prevention effects across the transition to early adulthood, a period of increased exposure to alcohol and other drug use. This paper describes the protocol for the CAP long-term follow-up study which will determine the effectiveness of universal, selective and combined alcohol misuse prevention up to 7 years post intervention, and across the transition from adolescence into early adulthood., Methods: A cluster randomized controlled trial was conducted between 2012 and 2015 with 2190 students (mean age: 13.3 yrs) from 26 Australian high schools. Participants were randomized to receive one of four conditions; universal prevention for all students (Climate); selective prevention for high-risk students (Preventure); combined universal and selective prevention (Climate and Preventure; CAP); or health education as usual (Control). The positive effect of the interventions on alcohol use at 12-, 24- and 36-month post baseline have previously been reported. This study will follow up the CAP study cohort approximately 5- and 7-years post baseline. The primary outcome will be alcohol use and related harms. Secondary outcomes will be cannabis use, alcohol and other drug harms including violent behavior, and mental health symptomatology. Analyses will be conducted using multi-level, mixed effects models within an intention-to-treat framework., Discussion: This study will provide the first ever evaluation of the long-term effectiveness of combining universal and selective approaches to alcohol prevention and will examine the durability of intervention effects into the longer-term, over a 7-year period from adolescence to early adulthood., Trial Registration: This trial was registered in the Australian New Zealand Clinical Trials Registry ( ACTRN12612000026820 ) on January 6th 2012.

Background Evidence regarding the association between adolescent internalising symptoms and school non-completion has been limited and inconclusive. Aims To examine whether depressive and anxious symptoms at secondary school entry predict school non-completion beyond confounders and whether associations differ by baseline academic functioning. Method We used logistic regression to examine associations between depressive and anxious symptoms in grade 7 (age 12-14) and school non-completion (age 18-20) in 4962 adolescents. Results Depressive symptoms did not predict school non-completion after adjustment, but moderation analyses revealed an association in students with elevated academic functioning. A curvilinear association was found for anxiety: both low and high anxious symptoms predicted school non-completion, although only low anxiety remained predictive after adjustment. Conclusions Associations between internalising symptoms and school non-completion are modest. Common school-based interventions targeting internalising symptoms are unlikely to have a major impact on school non-completion, but may prevent non-completion in selected students., Competing Interests: Declaration of interestNone., (© The Royal College of Psychiatrists 2017.)

Background: A compulsivity spectrum has been hypothesized to exist across Obsessive-Compulsive disorder (OCD), Eating Disorders (ED), substance abuse (SA) and binge-drinking (BD). The objective was to examine the validity of this compulsivity spectrum, and differentiate it from an externalizing behaviors dimension, but also to look at hypothesized personality and neural correlates., Method: A community-sample of adolescents (N=1938; mean age 14.5 years), and their parents were recruited via high-schools in 8 European study sites. Data on adolescents' psychiatric symptoms, DSM diagnoses (DAWBA) and substance use behaviors (AUDIT and ESPAD) were collected through adolescent- and parent-reported questionnaires and interviews. The phenotypic structure of compulsive behaviors was then tested using structural equation modeling. The model was validated using personality variables (NEO-FFI and TCI), and Voxel-Based Morphometry (VBM) analysis., Results: Compulsivity symptoms best fit a higher-order two factor model, with ED and OCD loading onto a compulsivity factor, and BD and SA loading onto an externalizing factor, composed also of ADHD and conduct disorder symptoms. The compulsivity construct correlated with neuroticism (r=0.638; p ≤ 0.001), conscientiousness (r=0.171; p ≤ 0.001), and brain gray matter volume in left and right orbitofrontal cortex, right ventral striatum and right dorsolateral prefrontal cortex. The externalizing factor correlated with extraversion (r=0.201; p ≤ 0.001), novelty-seeking (r=0.451; p ≤ 0.001), and negatively with gray matter volume in the left inferior and middle frontal gyri., Conclusions: Results suggest that a compulsivity spectrum exists in an adolescent, preclinical sample and accounts for variance in both OCD and ED, but not substance-related behaviors, and can be differentiated from an externalizing spectrum.

Background: Adolescent substance use is associated with both earlier childhood behavioural problems and serious lifetime addiction problems later in life., Aims: To examine whether, and through which mechanisms, targeting risk factors in early childhood prevents substance use across adolescence., Method: Disruptive kindergarten boys (n = 172) living in Montreal were randomly allocated to a preventive intervention and a control condition. The intervention was delivered over 2 years (7-9 years of age) with two main components: (a) social and problem-solving skills training for the boys; and (b) training for parents on effective child-rearing skills., Results: Adolescent substance use, up to 8 years post-intervention, was reduced in those who received the intervention (d = 0.48-0.70). Of most interest, the intervention effects were explained partly by reductions in impulsivity, antisocial behaviour and affiliation with less deviant peers during pre-adolescence (11-13 years)., Conclusions: Adolescent substance use may be indirectly prevented by selectively targeting childhood risk factors that disrupt the developmental cascade of adolescent risk factors for substance use.

Objective: The current paper aims to review findings from developmental research that are related to adolescent substance-use and are considered key for improving theory and developing effective prevention., Method: A selective literature review of relevant developmental studies on adolescent substance-use was conducted., Results: Studies in epidemiology and developmental science focusing on developmental onset, developmental transitions, comorbidity among disorders, and endophenotypes have identified important trends, risk-factors for and consequences of adolescent substance-use, which have informed theoretical models of addiction. Furthermore, they have informed clinical practice by identifying childhood disorders and personality characteristics that can be targeted preventatively before substance-use problems have their onset., Conclusions: Developmental research has contributed significantly to the understanding of aetiology and treatment of substance-use disorders. By targeting early liability factors rather than substance-use problems later in adolescence, interventions could reduce the adverse impact substance-use has on the developing brain as well as other associated harms.